Automatic shut-off valve

Abstract

An improved automatic shut-off valve that allows the temperature of discharged water to be adjusted by rotating the valve operating handle. The means for shutting off the discharge of water is simplified by attaching a valve closure member directly to a piston which is pushed downward manually to initiate flow and then forced upward by a spring to seat the valve closure member and stop the water flow. The piston moves axially inside a piston cylinder that has a hole in its bottom, and a pin connected to the piston sits in the hole. The clearance between the hole and pin determines the rate at which water can flow into the cylinder, thereby controlling the rate at which the piston is returned to its normally shut position by the spring.

What is claimed is: 
     
       1. An automatic shut-off valve comprising in combination: a valve body having an upper end and a lower end, first and second inlet means in the lower end of said valve body for receiving hot and cold water supplied to said valve, said valve body having at least one outlet through which discharged water flows;   a piston cylinder within said valve body, said cylinder having upper and lower ends;   a piston slidably disposed within said cylinder and having a larger effective area at its bottom end than its top end;   a spring arranged so as to urge said piston upward;   a first passageway for leading hot and cold water from said inlet means to a first volume of said cylinder above said piston;   a second passageway for leading hot and cold water from said inlet means to a second volume of said cylinder below said piston, said second passageway being arranged so that the rate of water flow into said second volume is a fraction of the rate of water flow via said first passageway into said first volume;   a third passageway for passing water from said second volume to said first volume around said piston;   means on said piston for substantially preventing flow of water from said second volume to said first volume via said third passageway when said piston is moving up in said cylinder;   a valve opening for passing mixed water from said first volume to said at least one outlet;   a valve seat in the upper end of said piston cylinder surrounding said valve opening;   a valve closure member attached to the upper portion of said piston in position to engage said valve seat when said piston moves upwardly in said piston cylinder;   a stem slidably attached to said valve body and arranged to engage and push said valve closure member down so as to open said valve opening;   a valve operating handle attached to said stem to facilitate pushing said stem downward so as to open said valve opening; and   adjustable valve means between said first and second inlet means and said cylinder for varying the proportion of hot and cold water delivered from said first and second inlet means to said first volume via said first passageway, whereby to control the temperature of mixed water discharged via said at least one outlet.   
     
     
       2. A valve according to claim 1 wherein said adjustable valve means comprises a mixing valve member attached to the bottom end of said piston cylinder and positioned directly above first and second orifices formed by said first and second inlet means, said mixing valve member being contoured so that as it is rotated it will simultaneously (a) increasingly block one orifice, and (b) increasingly unblock the other orifice, thereby changing the ratio of inlet hot and cold water to provide discharge water with a desired temperature. 
     
     
       3. A valve according to claim 1 wherein said second passageway comprises a hole in the bottom end of said cylinder and a pin attached to said piston and disposed in said hole, said pin being sized so that a small clearance is formed between it and the perimeter of said hole which serves as a bleed for conducting water through said hole into said second volume. 
     
     
       4. A valve according to claim 1, wherein said adjustable valve means comprises means attached to the bottom of said cylinder for inversely blocking and unblocking said first and second inlets as said cylinder is rotated relative to said valve body, and means for rotatably mounting said cylinder in said valve body. 
     
     
       5. A valve according to claim 4 wherein said stem is rotatable relative to said valve body, and further comprising: means coupling said stem and cylinder so that said cylinder will rotate with said stem.   
     
     
       6. A valve according to claim 5 further including spring means urging said stem out of engagement with said valve closure member; and means for stopping upward movement of said stem by said spring means after said valve closure member has engaged said valve seat and said stem has been disengaged from said closure member   
     
     
       7. A valve according to claim 1 further including spring means urging said stem away from said piston. 
     
     
       8. An automatic shutoff valve comprising: a valve body having first and second inlets for receiving hot and cold water and at least one outlet for discharging a mixture of hot and cold water;   a piston cylinder within said valve body, said cylinder having first and second opposite ends and being arranged so as to provide a first passageway between it and said valve body which communicates with said first and second inlets, said cylinder also having a hole at its second end communicating with said first and second inlets, and at least one side port communicating with said passageway;   an annular valve seat at said first end of said cylinder surrounding a discharge opening for passing water from said cylinder to said at least one outlet;   a piston slidably disposed within said cylinder, said piston having first and second opposite ends facing said first and second ends, respectively, of said cylinder, said piston being sized so as to provide a second passageway between it and said cylinder for flow of water from said hole to said discharge opening, said cylinder having a larger effective area at its second end than its first end;   a valve closure member attached to said first end of said piston and arranged so as to fully engage said valve seat and close off said discharge opening when said piston is moved toward said first end of said cylinder;   a peripheral groove in said piston;   at least one aperture in said piston leading from said groove to said first end of said cylinder;   an O-ring disposed in said groove, said groove and O-ring being sized so that said O-ring engages the inside surface of said cylinder and also so that it can move in said groove axially of said piston, whereby said O-ring will tend to move in said groove (a) toward said first end of said piston when said piston moves toward said second end of said cylinder and (b) toward said second end of said piston when said piston moves toward said first end of said cylinder, said O-ring effectively blocking said at least one aperture when it moves in said groove toward said first end of said piston;   a valve operating stem;   means slidably mounting said stem in coaxial relation to said valve closure member and said piston;   a piston spring urging said piston upward and away from said second end of said cylinder;   a handle attached to said stem for pushing said stem toward said closure member and said second end of said cylinder;   means on said valve closure member in position to be engaged by said stem and to cause said closure member to be moved by said stem away from said valve seat toward said second end of said cylinder, whereby water will flow from said first and second inlets to said at least one discharge opening via said first passageway;   a pin attached to said piston and projecting into said hole in said cylinder, said pin being undersized relative to said hole so as to provide a bleed passageway therebetween whereby water may flow from said first and second inlets into the space -between said piston and said second end of said cylinder, whereby after said piston has been moved so as to disengage said valve closure member from said valve seat and said stem has been disengaged from said piston, flow of water into said space via said bleed passageway will gradually cause the piston to be hydraulically forced to move said valve closure member into flowblocking engagement with said valve seat;   means rotatably mounting said cylinder in said valve body; and   valve means on said cylinder for inversely blocking and unblocking said first and second inlets, respectively, as said cylinder is rotated relative to said valve body, whereby to vary the mixture of hot and cold water passing from said inlets to said at least one outlet.   
     
     
       9. A valve according to claim 8 wherein said valve body comprises a first upper section and a second lower section mated together by a screw thread connection, and further wherein said at least one outlet is formed in said first upper section and said first and second inlets are in said second lower section. 
     
     
       10. A valve according to claim 9 further including a valve spout communicating with said at least one outlet by means removably attached to said upper valve body. 
     
     
       11. A valve according to claim 10 wherein said first and second inlets comprise first and second separately formed members disposed in said second lower section of said valve body. 
     
     
       12. A valve according to claim 9 further including a hollow core member rotatably disposed in said first upper section of said valve body, and further wherein said cylinder is attached to said core member in spaced relation to said second lower section of said valve body. 
     
     
       13. A valve according to claim 12 further including a valve stem guide mounted within said hollow core member, and means for preventing rotation of said valve stem relative to said hollow core member while permitting axial movement of said stem relative to said hollow core member. 
     
     
       14. A valve according to claim 13 wherein said valve seat is part of a separately formed member which is mounted within said core member. 
     
     
       15. A valve according to claim 14 wherein said separately formed member is screwed into said core member. 
     
     
       16. A valve according to claim 8 wherein said stem is rotatable relative to said valve body, and further including means for causing said cylinder to rotate with said stem, and means for limiting rotation of said valve stem relative to said valve body. 
     
     
       17. A valve according to claim 16 wherein said means for limiting rotation comprises first means rotatable with said valve stem and second means fixed with respect to said valve body. 
     
     
       18. A valve according to claim 17 further including a housing surrounding and attached to said valve body, said second means being attached to said housing. 
     
     
       19. A valve according to claim 17 wherein said first means comprises a first disk having a first stop member engagable with said second means, a second disk having a second stop member engagable with said second means, and means releasably locking said first and second disks to one another. 
     
     
       20. A valve according to claim 9 wherein said first and second inlets comprise first and second separately formed orifice members removably positioned within said second lower section of said valve body. 
     
     
       21. A valve according to claim 8 further including a housing surrounding said valve body, a faucet spout within said housing, and means connecting said faucet spout to said at least one outlet. 
     
     
       22. A valve according to claim 8 further including means for disengaging said valve operating handle from said valve operating stem when said handle has been depressed to a predetermined bottom-limit position, whereby said stem is free to return to its initial position independent of whether or not said handle has returned to its original upwardly position. 
     
     
       23. A valve according to claim 22 wherein said disengaging means comprises in combination: a first member connected to the bottom side of said valve operating handle and having a lower end and an upper end, said member having a diametric slot in said lower end with two latch members pivotally mounted within said slot;   a spindle sleeve surrounding said stem and having an upper end and a lower end, said lower end being slidably mounted in the upper end of said valve body, and said upper end of said sleeve being securely attached to said member;   a valve handle spring located between said valve handle and the upper end of said valve body so as to bias said handle upward and away from said valve body; and   a second member fastened to said valve body and positioned so as to coact with said latch members, whereby when said valve handle is depressed so as to cause said latch members to engage and depress said stem, said latch members will pivot so as to disengage said stem and allow said stem to return to its original position.   
     
     
       24. An automatic shutoff valve comprising: a valve body having first and second inlets for receiving hot and cold water and at least one outlet for discharging a mixture of hot and cold water;   a piston cylinder within said valve body, said cylinder having first and second opposite ends and being arranged so as to provide a first passageway between it and said valve body which communicates with said first and second inlets, said cylinder also having a hole at its second end communicating with said first and second inlets, and at least one side port communicating with said passageway;   an annular valve seat at said first end of said cylinder surrounding a discharge opening for passing water from said cylinder to said at least one outlet;   a piston slidably disposed within said cylinder, said piston having first and second opposite ends facing said first and second ends, respectively, of said cylinder, said piston being sized so as to provide a second passageway between it and said cylinder for flow of water from said hole to said discharge opening, said cylinder having a larger effective area at its second end than its first end;   a valve closure member attached to said first end of said piston and arranged so as to fully engage said valve seat and close off said discharge opening when said piston is moved toward said first end of said cylinder;   a peripheral groove in said piston;   a resilient sealing member in said groove arranged so as to (a) allow flow of water past said piston when said piston is displaced toward said second end of said cylinder and (b) block flow of water past said piston when said piston moves toward said first end of said cylinder;   a valve operating stem;   means slidably mounting said stem in coaxial relation to said valve closure member and said piston;   a piston spring urging said piston upward and away from said second end of said cylinder;   a handle attached to said stem for pushing said stem toward said closure member and said second end of said cylinder;   means on said valve closure member in position to be engaged by said stem and to cause said closure member to be moved by said stem away from said valve seat toward said second end of said cylinder, whereby water will flow from said first and second inlets to said at least one discharge opening via said first passageway;   a pin attached to said piston and projecting into said hole in said cylinder, said pin being undersized relative to said hole so as to provide a bleed passageway therebetween whereby water may flow from said first and second inlets into the space between said piston and said second end of said cylinder, whereby after said piston has been moved so as to disengage said valve closure member from said valve seat and said stem has been disengaged from said piston, flow of water into said space via said bleed passageway will gradually cause the piston to be hydraulically forced to move said valve closure member into flowblocking engagement with said valve seat;   means rotatably mounting said cylinder in said valve body; and   valve means on said cylinder for inversely blocking and unblocking said first and second inlets, respectively, as said cylinder is rotated relative to said valve body, whereby to vary the mixture of hot and cold water passing from said inlets to said at least one outlet.